Self-steering submarine suction cleaner



H. H` BABCOCK SELF-STEERING SUBMARINE SUCTION CLEANER June 20, 1961 5 Sheets-Sheet 1 Filed Feb. 8, 1960 T1 :'JU-

June 20, 1961 H. H. aABcocK SELF-STEERING SUBMARINE SUCTION CLEANER 5 Shegts-Sheet 2 Filed Feb. 8, 1960 June 20, 1961 H. H. BABcocK SELF-STEERING SUBMARINE SUCTION CLEANER Filed Feb. 8, 1960 54 Sheets-Sheet 3 ENTOR flcocf( June 20, 1961 H. H. BABcocK 2,988,762

SELF-STEERING SUBMARINE SUCTION CLEANER Filed Feb. 8, 1960 5 Sheets-'Sheet 4 TETES' 4a 1 VENTOR: ///s/ .545606K ATTORN June 20, 1961 H. H. BABCOCK 2,988,762

SELF-STEERING SUBMARINE SUCTION CLEANER Filed Feb. 8, 1960 5 Sheets-Sheet 5 Tlc'jly INVENTOR /Gf/ i Aacoc/f ATTORNEY I United States Patent O 2,988,762 SELF-STEERING SUBMARINE SUCTION CLEANER Hugh H. Babcock, R.D. 1, Katonah, N.Y. Filed Feb. 8, 1960, Ser. No. 7,218 9 Claims. (Cl. 1s-1.7)

The present invention relates to submarine cleaning apparatus adapted for the cleaning of the bottom surfaces of pools, tanks, and the like and more particularly relates to self-steering submarine suction cleaners.

Among the objects of the present invention are to provide effective self-steering submersible suction cleaners for automatically cleaning the bottoms of tanks and the like, and particularly well adapted for use in swimming pools. The present invention provides further improvements over the submarine cleaner apparatus as disclosed and claimed in my. prior application Serial No. 519,961, filed July 5, 1955, now Patent No. 2,923,954.

During use, swimming pools collect a large amount of dust, dirt and sediment which tend to build up a mucky silt layer on the floor of the pool. To maintain sanitary conditions and to have the water pleasant for swimming and prevent Waders from stirring up clouds of silt, as they walk about, it is necessary to thoroughly clean the pool oor at frequent intervals.

Among the many advantages provided by the self-steering submarine cleaner embodying the present invention are those resulting from the fact that the cleaner is automatic in operation and highly effective in cleaning a pool iioor as it travels back and forth along an overlapping zigzag path extending from one wall of the pool to the other and traversing across the area of the bottom. In this example of the invention a reversible driving motor is mounted in the chassis of the cleaner and drives the cleaner back and forth as Well as turning a centrifugal pump which is adapted to be rotated in either direction.

The axes of the rolling members which engage the bottom of the pool and support the cleaner remain fixed in position on the chassis. An advantageous steering action is provided by the cooperation of offset wall bumping elements and of the driving mechanism itself. After the cleaner has traversed across the pool oor one of the bumping elements engages the wall while the driving mechanism continues for a brief period to drive in the same direction. As a result, the body of the cleaner is turned slightly. A reversing sensor element then causes the cleaner to begin driving across the pool floor along a return path which is at a slight angle with respect to the initial path. In this way an accurate traversing action is provided by the cleaner and requiring the use of very few moving parts, resulting in a dependable trouble-free operation over long periods of time. l

In this specification and the accompanying drawings is shown and described a preferred embodiment of the present invention which consists in the features of construction, arrangements of parts, and elements as exemplified in this embodiment. However, it is to be understood that this described embodiment is not intended to be exhaustive nor limitingV of the scope of the invention, but on the contrary is given for purposes of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of applying the invention in practical use and modifying and adapting it in various forms, each as may be best suited to the conditions of a particular use.

The various features, aspects and objects of the present invention will be more fully understood from a consideration of this specification in conjunction with the drawings, in which: I

FIGURE 1 is a plan view of a swimming pool schematically illustrating the pathway followed by the selfice steering cleaner of the present invention as it progressively cleans the bottom surface; Y

FIGURE 2 is a plan view showing the submarine cleaner of the present invention in greater detail and illustrating the advantageous self-steering action;

FIGURE 3 is a side elevational view corresponding with FIGURE 2 and showing the instant after it has reversed direction and started across the pool iloor in the opposite direction;

FIGURE 4 is an end View of the cleaner of FIGURE 2 as seen looking in a direction from the left edge of the sheet;

FIGURE 5 is an enlarged sectional view taken along the line 5-5 of FIGURE 2 showing the action of the scrubbing brushes as the cleaner moves toward the right;

FIGURE 6 is similar to FIGURE 5 and illustrates the reversed action of the scrubbing brushes as the cleaner moves toward the left;

FIGURE 7 is an enlarged partial sectional view taken along the line 7-7 of FIGURE 3 illustrating the off switch and reversing switch and the double worm gear drive;

FIGURE 8 is a partial plan sectional view of the double worm gear drive taken along the line 8 8 in FIGURE 7 and in FIGURE 9;

FIGURE 9 is a partial elevational sectional view of the double worm gear drive taken along the line 9--9 of FIGURE 8;

FIGURE 10 is a schematic circuit diagram illustrating the electrical connections; and

FIGURE 11 is a schematic circuit diagram illustrating the use of one motor for driving the cleaner and a second motor for driving the pump.

As illustrated in FIGURE l, in operation the cleaner, generally indicated at 2, is lowered into a corner of a pool 3 and is directed so as to travel back and forth across the narrower dimension of the pool. A lift rope 4 is secured to a central carrying handle 6 and is used to lower the cleaner into its starting position. The self-steering mechanism guides the cleaner back and forth between opposite side walls 8 and 10. An overlapping zig-Zag path 12 is followed so as to produce a thorough cleaning of the lloor 14 of the pool as indicated by the dashed centerline and the arrowheads thereon.

A rectangular pool is illustrated in FIGURE l. However, it is an advantage of this invention that it does provide effective self-steering operation in round, kidneyshaped and other free-form pools or tanks. For example, in round pools the cleaner traverses along chords which are successively changed in orientation with respect to the beginning point and thereby cleans the entire pool bottom. In other words, the traverses progress around the pool so that every other contact with the wall of the pool effectively boxes the compass.

There is a shut-off sensor 16 projecting from one side of the cleaner. When the cleaner is initially positioned, this sensor 16 is directed away from the adjacent end wall 11S of the pool, so that the cleaner'continues progressing toward the opposite end wall 20. After the cleaner has rtraversed over the area of the pool floor, then the sensor 16 is activated by engagement with the wall 20 and the cleaner shuts itself off. In round and some free-form pools the cleaner continues Ain operation until the user turns it olf.

As shown in FIGURES 2, 3 and 4, the reversible drive motor 22 formsV the central part of the chassis. In its low centralized position the motor affords a low center of gravity for the cleaner as a whole. Secured to one end of the motor is a double Worm and ygear drive assembly compartment 24. At the other end is a centrifugal pump compartment 26 and a suction hood 28 which extends out symmetrically from opposite sides of the motor so as to clean a wide pathway on each pass of the cleaner. These compartments 24 and 26 are clamped against opposite ends of the motor by means of four through bolts 30 as seen most clearly in FIGURES 7 and 9. A pair of triangular plates 31 and 32 project upwardly from these compartments forming mounting brackets for the handle 6.

Rolling members for supporting and driving the cleaner are provided in the form of a pair of idler wheels 34 mounted near the bottom of the pump compartment. A pair of driving wheels 36 are mounted on the drive axle 38 which extends out through water-tight seals 40l on opposite sides of the worm gear drive assembly compartment 24.

In order to drive the cleaner, a worm 42. on one end of the motor shaft 44 engages a gear 45 on a vertical intermediate shaft 46. Another worm 48 on this intermediate shaft engages a gear 50 secured to the drive axle 38. It will be appreciated that the axes of the rolling members 34 and 36 are xed so that the cleaner follows a straight course during each pass back and forth across the pool floor.

For purposes of turning the body of the cleaner through a small angle oa between each pass, there are a pair of laterally offset fixed bumper elements 52 and I54, one at each end of the cleaner. The `bumper 54 is a rod adjustably mounted in a socket 56 at one end of the suction hood 28. By loosening a set screw 58 and sliding the rod 54 into or out of the socket 56, the turn angle is readily adjusted, as will be explained in greater detail further below. This adjustment changes the angle between adjacent portions of the traversing path 12 so as to provide optimum coverage of the pool oor.

The other bumper element 52 is formed by an adjustable rod mounted near the end of a horizontal bridge member 60. This bridge member comprises a channel fastened across the top of a switch compartment 62 which is positioned above the worm and gear assembly compartment 24. The rod 52 is fitted through aligned holes in the flanges 63 and 64 of the bridge member 60 and is held in adjusted position by a set screw 66. It will be noted from FIGURES 2 and 4 that the bumper elements 52 and 54 are offset by equal amounts from the centerline of the cleaner, thus producing equivalent turning action at opposite ends of each pass.

In operation, when the cleaner approaches one of the pool side walls 8 or 10, as shown by the dashed outline 67, one of these bumper elements strikes the wall and provides a pivot point 68 about which the cleaner turns itself as indicated by the turning arrow in FIGURE 2, at the lower right corner. This turning of the cleaner is accomplished by the driving wheels 36 which continue to urge the body of the cleaner toward the wall thus swinging it about the point 68 until a reversing sensor slide-rod element 70 engages the wall and is depressed by the continued forward movement of the cleaner. At this instant of time the motor 22 reverses and the cleaner starts of`1r on its next pass across the pool floor.

It will be appreciated that the turning angle a between successive passes across the pool floor is increased by adjusting the bumper elements '52 and 54 so that they project farther ahead of the respective ends of the slide-rod reversing sensor 70.

This reversing sensor 70 is mounted for reciprocating movement and one end portion passes through the switch compartment 62 wherein it actuates a swinging arm 71. This arm is mounted on a pivot 72, and its opposite end 65 has an eye 69 therein loosely surrounding the sliderod 70.

There is a fixed collar on the slide-rod which engages the end 65 of the swinging arm and a small coil spring (not shown) holds the end 65 against the collar. The purpose of this coil spring is to accommodate over-travel of the slide-rod. Thus, reciprocating movement of the slide-rod causes the arm 71 to swing about its pivot. Within the switch compartment are four switches, such as Microswitch units, 73, 74, 75 and 76, each having an actuating button 77, as will be understood. There are four adjustment screws carried by the arm 71 adapted to engage and actuate the respective buttons 77. The operation of these respective switches will be explained in detail further below in connection with FIGURE 10. A guide 78 projects up from the suction hood so as to support the opposite end portion of the slide-rod 70.

In order to clean the silt from the pool floor, a pair of long parallel brushes 80 and 81 are mounted in a holder 82 pivotally connected to the lower ends of a pair of swinging toggle legs 83 and 84. The upper ends of toggle legs fit up into openings 85 and 86 in the top of the suction hood 28 and are held in place by cross pins. Springs 87 surround each of these toggle legs and hold the brushes firmly down against the bottom.

As shown in FIGURES 5 and 6, one or the other of these brushes always is shifted over against the rear edge of the hood with respect to the direction of travel. For example, as shown in FIGURE 5, the brush 80 is closely adjacent to the lower rear edge 88 of the hood. Thus, the rear of the hood is effectively blocked and the inrush of water occurs beneath the front edge 89 where it is most effective in drawing the slit into the intake 90 of the pump. This blocking action by the rearward brush has the advantage of reducing the pumping capacity necessary to obtain the desired velocity beneath Ithe respective edges 88 and 89.

The pump impeller 91 is circular and has a pair of radially extending discharge openings 92 from which the liquid is discharged by centrifugal force into the interior 97 of the pump compartment 26. This type of impeller with a pair of opposed openings 92 has been found to be virtually free from any tendency to clog itself by leaves, grass or the like. Discharge openings extending radially enable a pumping action to occur in either direction of rotation.

The shaft 44 passes through a seal 95 into the pump compartment. It will be understood that for some applications it may be desirable to have one motor to operate the driving mechanism and another motor to operate the pump.

As shown in FIGURE l0, the motor 22 is of the induction type including a rotor 96 and a main stator winding 98 which is energized from the power lines 99 and '100 by means of the switch 73 or 74, one of which is closed while the other is open.

As shown in FIGURE 11, the motor 22 drives the cleaner and a second motor 110 is provided for driving the centrifugal pump 26, which in this illustrative embodiment of the invention is arranged to rotate always in the same direction.

A reversing winding 102 is also connected to the power lines through the switches 75 and 76, which comprise a reversing switch 103.

In operation, as the sensor slide-rod 70 is moved by contact with a wall 8 or 10, the arm 71 first opens one of the main switches 73 or 74, this allows the rotor to slow down so that the centrifugal switch 104 closes. The reversing switch 103 is then actuated so that both of the switches 75 and 76 reverse position, and finally the other main switch 74 or 73 is closed, depending upon the direction. Thus, the direction of rotation is reversed.

Instead of reversing the motor, the drive mechanism itself can be reversed, for example as shown in my prior application. A capacitor 106 is in circuit with the reversing winding to provide the desired phase relationship with the main winding, and the centrifugal switch is opened when the rotor reaches substantially full speed in either direction.

In order to turn off the cleaner when it reaches the far end 20 of the pool, there is a shut-off sensor 16 extending out through a ange 105 at the opposite end of thebridge member-60 from the lfixed bumper element 52. This shut-off sensor is adapted to slide inwardly upon contact with the wall Z0, thus opening a switch 106 in one of the power lines. An electrical cord 108 runs up from the cleaner to a suitable outlet above the water. The outlet 93 from the pump compartment is connected to a filter bag 94 or to a discharge hose, whichever is convenient.

From the foregoing it will be understood that the selfsteering submarine cleaner of the present invention described above is well suited to provide the many advantages set forth, and since different embodiments may be made of this invention and as the apparatus herein described may be varied in various parts, all without departing from the scope of the invention, itis to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense and that in certain instances, some of the features of the invention may be used without a corresponding use of other features, or without departing from the scope of the invention.

I claim:

1. A self-steering submarine suction cleaner adapted to clean the bottom surface of a tank by steering itself along a zig-zag course extending back and forth between opposite side walls of the tank, said cleaner comprising a reversible electric motor, rotating drive members mounted on the cleaner for rotation about fixed axes and adapted to support and to drive the cleaner, drive mechanism connecting said motor to said rotating drive members, first and second fixed bumper elements at opposite ends of the cleaner, said bumper elements both being offset laterally from the centerline of the cleaner on the same side of the cleaner, said first and second bumper elements projecting respectively ahead of the cleaner as it moves in its respective directions for engaging the respective side walls of the tank to provide pivot points about which the cleaner turns itself :as the drive members continue driving the cleaner toward the engaged wall, first and second reversing control means at opposite ends of the cleaner for engaging the respective side walls after the cleaner has turned itself by a predetermined amount for reversing the direction of movement, -a suction pump, and a suction hood closely adjacent to the bottom of the tank communicating with said suction pump for cleaning the bottom of the tank.

2. A self-steering submarine suction cleaner adapted to clean the bottom surface of a tank by steering itself along a zig-zag course extending back and forth between opposite side walls of the tank, said cleaner comprising a reversible electric motor, rotating drive members mounted on the cleaner for rotation about fixed axes and adapted to support and to drive the cleaner, drive mechanism connecting said motor to said rotating drive members, first and second fixed bumper elements at opposite ends of the cleaner, said bumper elements both being offset laterally from the centerline of the cleaner on the same side of the cleaner, said first and second bumper elements projecting respectively ahead of the cleaner as it moves in its respective directions -for engaging the respective side walls of the tank to provide pivot points about which the cleaner turns itself as the drive members continue driving the cleaner toward the engaged wall, first and second sensor control means at opposite ends of the cleaner for engaging the respective side walls after the cleaner has turned itself by a predetermined amount, reversing switch means actuated by said sensor control means for reversing the motor, a suction pump, and a suction hood closely adjacent to the bottom of the tank communicating with said suction pump for cleaning the bottom of they tank.

3. A self-steering submarine suction cleaner as claimed in claim 2 and wherein said suction hood includes an elongated brush therein, spring means urging said brush against the bottom of the pool, and a movable mounting 6 for said brush, whereby said brush changes position for effectively blocking the space beneath the rear of said hood with respect to the direction of movement.

4. A self-steering submarine suction cleaner as claimed in claim 3 and' wherein said suction hood includes a brush holder having a pair of elongated parallel brushes, a plurality of toggle legs swingably mounted atv their upper endsV and 'pivotally connected to said brush holder at points between said brushes.

5. A self-steering submarine suction cleaner as claimed in claim 2 and wherein said drive mechanism comprises a first Worm driven by said motor, an auxiliary shaft hav-ing a gear thereon driven by said worm and a second worm on said auxiliary shaft, an axle carrying said rotating members and having a second gear thereon driven by said second worm, thereby providing a substantial speed reduction from said motor to said axle.

6. A self-steering submarine suction cleaner as claimed in claim 1 and including a second motor for driving said suction pump.

7. A self-steering submarine suction cleaner as claimed in claim 1 and wherein said rotating drive members comprise a pair of wheels, said bumper elements being offset farther from the centerline than said wheels.

8. A self-steering submarine suction cleaner adapted to clean the bottom surface of rectangular, round, kidneyshaped and free-form swimming pools by steering itselfv along successive progressive traverses at a small angle with respect to successive preceding traverses to clean substantially the entire bottom of the pool, said cleaner comprising a reversible electric motor, rotating drive members mounted on the cleaner for rotation about xed axes and adapted to support and to drive the cleaner, drive mechanism connecting said motor to said rotating drive members, -frst and second fixed bumper elements at opposite ends of the cleaner, said bumper elements both being offset laterally from the centerline of the cleaner on the same side of the cleaner, said first and second bumper elements projecting respectively ahead of the cleaner as it moves in its respective directions for engaging a wall of the pool ahead of the cleaner to provide respective pivot points about which the cleaner turns itself as the drive members continue driving the cleaner toward the engaged wall, first and second sensor means at opposite ends of the cleaner for engaging the respective side walls after the cleaner has turned itself by a predetermined amount, reversing means actuated by said sensor means for reversing the motor, a suction pump, and a suction hood closely adjacent to the bottom of the tank communicating with said suction pump for cleaning the bottom of the tank.

9. A self-steering submarine suction cleaner adapted to clean the bottom surface of a tank by steering itself along a zig-zag course extending back and forth between opposite side walls of the tank, said cleaner comprising a reversible electric driving mechanism, rotating drive members mounted on the cleaner for rotation about fixed axes and adapted to support and to drive the cleaner, said driving mechanism being connected to said rotating drive members, first and second xed bumper elements at opposite ends of the cleaner, said bumper elements both being offset laterally from the centerline of the cleaner on the same side of the cleaner, said iirst and second bumper elements projecting respectively ahead of the cleaner as it moves in its respective directions for engaging the respective side Walls of the tank to provide pivot points about which the cleaner turns itself as the drive members continue driving the cleaner toward the engaged wall, first and second reversing control means at opposite ends of the cleaner for engaging the respective side walls after the cleaner has turned itself by a predetermined amount, switch mechanism actuated by said reversing control means and connected to said reversible driving mechansm for reversing the direction of v'1 movement after actuation of said switch mechanism, a suction pump, and a suction hood closely adjacent to the bottom of the tank communicating with said suction pump for cleaning the bottom of the tank.

References Cited in the le of this patent UNITED STATES PATENTS 1,935,158 Lumley Nov. 14, 1933 FOREIGN PATENTS Germany Sept. 4, 1923 France Jan. 5, 1932 

